Brush mounting for dynamoelectric machines



July 16, 1935. H. R. PATTERSON.

BRUSH MOUNTING FOR DYNAMO-ELECTRIC MACHINES Filed May 26, 1953 flaw/y E. Pa fi e/n90 Patented July 16, 1935 r UNITED STATES. PATENT OFFICE BRUSH MOUNTING FOR DYNAMO- ELECTRIC MACHINES Harry R. Patterson, Toledo, Ohio, assignor to The Electric Auto-Lite Company, Toledo, Ohio, a corporation of Ohio Application May 26, 1933, Serial No. 672,921

11 Claims. (Cl. 171-4324) This invention relates to electrical apparatus Figure 2 is an enlarged detailed view of the and more particularly to brush supporting struccombined brush support structure and end frame tures for use with dynamo electric machines comconstruction embodying the invention;

monly employed as part of the electrical equip- Figure 3 is a fragmentary detailed sectional 5 ment of motor vehicles. view taken substantially on the line 33 of Fig- 5 It is one of. the principal objects of this inure 2; vention to provide a combined end frame struc- Figure 4 i a fragmentary detailed Sectional ture for dynamo electric machines having a brush View taken substantially 011 e n O supporting member of novel construction. We

l- Another object is the provision of a combined u e 5 s an e a g d d tailed V ew w n brush holder support and bearing f th armathe brush holder mounting and means for limitture shaft of a dynamo electric machine. Anthe a r mhvement; oth r object of thi i ti is t provide an Figure 6 is a detailed sectional view taken subproved brush holder mounting simple and com- Stahtially On line of Figure 2.

i5 pact in construction which permits the ready IhaVe ShGWh the arrangement of y invention assembly and easy adjustment of the br h hold r as incorporated in a dynamo-electric machine bracket relative to the end frame construction. of the type commonly p y d or e n auto- A further object of thi i nt is t provide motive vehicle constructions, but it is to be una brush holder mounting such that on of the derstood that my invention is susceptible of other brush holders ca be adjusted l ti t th uses and thatI contemplate its utilization in any 20 other. arrangement wherever the same may be found to Another object is the provision of a brush applicableholder construction wherein the brush bracket Referring the drawing in de gu 1 is pivotally mounted and so constructed that obillustrates an embedimeht Of y 11111611111011 in a noxious hums or brush noi es are li i t d generator which includes a housing having end 25 The invention also contemplates the provision Plate Closures I! and the end p tes H and of means associated with the brush structure, an are p d With DOIUJIIS and a comend frame construction whereby the brush holder modetihg bearings for Supp t e Shaft 55 or bracket will be prevented from pressing against Which tulh Carries e fi e 5 T e no the commutator in case the brush becomes broken plates H and F2 are Preferably held in p a 011 or when the brush holder bracket reaches a prethe generator Casing 1/ Suitable means as, for determined position and this means includes eXample, Studs 57 Which eXtehd throughout t means to stop the angular position of the brush length of the Casing and receive retaining bracket with respect to th commutatgr nuts l3, thus holding these parts in assembled 23 The invention comprehends the provision of a relation construction of this character Where certain parts AS particularly illustrated in Figures 1 a d are made of sheet metal and capable of being the end Plate 12 is fcl'med to l p manufactured and assembled in large quantities a plurality of brushes for engagement with the th t the use of special tools as Well as to commutator 253. Ihe generator illustrated is of 40 facilitate interchangeability of parts for purpose the so-called third brush type having two main 40 of replacement or repam brushes 2! and 22 and an adjustable third brush Further objects and advantages are within the the posltlon of i brush npon the scope of this invention such as relate to the ari i i 2G djeteljmlm'ng we gen'zml rangement, operation and function of the related acbenstms of the geneiaml" 11' In the rran ement i us rate the Jr t I" 1 elements of the structure, to various details of a b it, b r a 6 15 provided with a centi a 1 c construct on and to combinations of parts, elee ments per se, and to economies of manufacture and numerous other features as will be apparent from a considerationv of the specification and drawing of certain forms of the invention, which may be preferred, in which:

a brush carrying structure for the brush In the particular generator construction illus- 50 trated, the brush supporting structure for main brush 22 is insulated as will be described, and F ure 1 is a side elevational view of the dybrush supporting structure for main brush is namo electric machine embodying my invention not insulated, but is grounded through cable is,

with certain parts broken away; while the brush supporting structure for the 5 third brush 23 is insulated from carrying plate 2?. The brush holder structures carrying the main brushes 2! and 22 are substantially the same as the structure carrying the third brush 23 and therefore only one structure will be described in detail. 7

The mounting for the brush 2! and supporting parts is particularly illustrated in Figure 3, in which two openings 30 and 3! are made in the end plate 52 to accommodate pins or stud shafts 32 and 33, the ends of the pins being knurled to insure snug fit of the pins in plate l2. The shaft 33 is provided with a shoulder portion 3 3 and a cylindrical tenon portion 35, the latter accommodating the brush holder frame 31, preferably of thin or sheet material, the latter being substantially of U-shaped configuration, the adja cent parallel legs 38 of which are provided with openings it? as illustrated in Figure 5 for mounting upon the cylindrical tenon 35. The brush is carried at the bight of the brush holder structure,'the latter being provided with'a threaded opening to receive the brush retaining screw 33, structure 3? being provided with an integral lip or lug portion 39 which acts as a seat for the brush 2 l A resilient member or spring Ail is providedtfor urging the brush holder and brush carried thereby into engagement with'the commutator of the dynamo-electric machine. This spring preferably comprises two sets of juxtaposed coil portions 43 and it spaced apart and preferably formed of one piece of wire, the loop joining the two sets of coils of the spring, as indicated at 45, being in engagement with a reduced portion 46 of stop pin 32, the free ends of the wire making up the spring il being turned outwardly at their extremities 5'5 and engaging the legs 38 of the brush holder structure per se. As will be seen from an examination of Figure 5, the spring 4! is constructed and connected to the brush holder 3? and the stop pin 32 in such a manner that the spring is under tension tending to rotate the brush holder 3? in a counterclockwise direction around the pivot pin or stud shaft 33 as the axis which tendency to rotation moves the brush 21 into resilient engagement with the commutator.

A feature of this invention resides in the manner of mounting the movable brush carrying member with respect to its support, so that a particular co action is present between the brush supporting member and said support so that obnoxious hurns or squeaks are eliminated. As a practical application of the invention, the movable brush supporting member 3'8 is provided with an opening 43 of particular configuration having certain surfaces in intimate contact with the pivot pin 33. n examination of Figure 5 of the drawing showing one form of the invention discloses the cylindrical portion of the opening '59 being of larger diameter than the diameter of pin 33, a second partial cylindrical portion of the opening 56 of lesser diameter than that of pin 33 and substantial tangential walls 5! joining the walls of the partial cylindrical openings. The inherent resiliency or tension in spring 4] urges the brush holder 3'3 to a position in which the periphery of the pivot pin 33 engages with the straight or tangential walls 5! of the opening 48 engaging the periphery of the pin. In effect the pin rests in a V-shaped opening, affording a line contact between the movable brush carrying member and its support, the spring 4,! being under tension urging the brush holder into intimate contact with its support, without excessive pressure of the brush upon the commutator thereby reducing brush wear. This construction eliminates any tendency of the brush holder to tilt or to change its position relative to the supporting pin as it is at all times urged by means of the spring 4! into a predetermined position which prevents tilting or sidewise movement of the brush with respect to the. commutator. It has'been found that through the use of .alconstruction of this nature, the consequent wear and'a'ny sparking of the commutator and brush is proportionately decreased by reason of the full area or line of contact being had at all times between the surfaces of the brush and commutator, and at the same time brush noises, as for example, humming and squeaking and the like, are substantially reduced or eliminated.

In the embodiment illustrated, the supporting mounting for each o-fthe three brush carrying or supporting structures is substantially the same. The method of mounting the pivot and stop pins carrying the brush structure 22 is modified in that the pivot pin 33' and stop pin 32 are insulatingly supported upon theplate l2 by means of insulating bushings 55 and 5'5, as particularly illustrated in Figure 4.

The movable thirdrbrush 23 and its supporting structure comprising the pivot pin 33 and the stop pin 32" are insulatingly supported upon the projections 28 formed upon the movable ring 27. In this form of mounting a series of washers of insulating material 58 are interposed between a reduced portion of the pin 32 and an opening in the projection 28 so as to completely insulate the brush and supporting structure from the brush holder ring 21, the end or pivot pin 33 being swagedover as at 6% to fixedly retain the supporting pin upon the projection 28.

In order to maintain the-movable brush 23 concentric with the commutator, the end plate I2 is provided with a shoulder 72 concentric with the axis of the journal bearing to receive the armature shaft IS, the brush holder plate 2'! be ing provided with struck-up portions l3 forming a multilated concentrically arranged flange snug- 1y engageable with shoulder '12 thus assuring that adjustment of the third or movable brush 23 will always be in a path concentric with the axis of the armature shaft. As particularly illustrated in Figure 2, the movable ring 21 is maintained in its adjustable position by frictional means consisting in the embodiment shown of spring clips having portions It frictionally engageable with a surface of ring 27, the clips being held in place by means of screws 18 threaded into the end plate l2. In other respects, means for supporting the brush holder and brush are the same as illustrated in Figure 5 and as hereinbefore described.

It is apparent that, within the scope of the invention, modifications and different arrangements may be made other than is herein disclosed, and the present disclosureiis illustrative merely, the invention comprehending all variations thereof. V

What I claim is:- l

1. In a device of the character disclosed, in combination, a plate; a supporting element carried by said plate; a member having closed slots provided with spaced non-circular wall portions, said supporting element projecting through and contacting with spaced portions of the non-circular walls of said slots; and means for urging said member into predetermined position with respect to said supporting element.

2. In a device of the character disclosed, in

combination, a plate; a supporting element fixed to said plate; a member having a plurality of arms having aligned closed slots formed with an.- gularly arranged spaced wall portions, said supporting element projecting through and contacting with spaced portions of the walls of said slots; and resilient means for urging said member into predetermined position with respect to said supporting element.

3. In a device of the character disclosed, in combination, a supporting element; a bracket supported upon said element, said bracket having projecting portions provided with openings having converging walls, portions of said supporting element projecting through and contacting with the converging Walls of said openings defining the position of said bracket with respect to the supporting element; and resilient means for urging said bracket into defined position with respect to said supporting member.

4. In a device of the character disclosed, in combination, a plate; a supporting element fixed to the plate; a bracket supported upon said element, said bracket having projecting leg portions provided with openings having converging walls, said supporting element projecting through and contacting with the converging walls of said openings defining the position of said bracket with respect to the supporting element; and a coil spring for urging said bracket into defined position with respect to said supporting member.

5. In a device of the character disclosed, in combination, a supporting element; a member movable relative to said supporting element having non-circular openings formed with opposed converging walls, said supporting element having portions projecting through and contacting with the opposed Walls of said openings; resilient means encircling the projecting portions of said support for urging said member into predetermined position with respect to said supporting element; and stop means for limiting the range of movement of said member.

6. In a device of the character disclosed, in combination, a plate; a stub shaft of cylindrical contour projecting from said plate; a bracket formed with projecting portions, said projecting portions being provided with aligned non-circular openings having converging walls, the converging Walls contacting with the cylindrical portion of said shaft for defining the relative position of the parts; and a spring engageable with said bracket and the shaft for urging the bracket to its defined position.

7. In a device of the character .disclosed, in combination, a plate; a supporting element fixed to the plate; a brush; a bracket supported upon said element having means to position and retain said brush, said bracket having portions provided with openings having converging Walls, said supporting member having portions projecting through and contacting with the converging walls of said openings defining the position of said bracket with respect to the supporting element; and a spring for urging said bracket and brush into defined position with respect to said supporting member.

8. In combination, an end plate for dynamoelectric machines having a pin projecting therefrom; a brush holder pivotally supported upon said pin, said brush holder being of U-shaped configuration and having a projecting lug adja cent its bight portion adapted to receive and position a brush; means for securing the brush to said holder, said brush holder having aligned openings formed with converging walls engageable with the supporting pin; and resilient means for urging said brush holder into predetermined pivotal relationship with respect to said pin.

9. The combination of a dynamo-electric machine having a frame and an armature and commutator having a shaft projecting therefrom; a brush coacting with said commutator; a brush holder pivota-lly supported upon a pin carried by said frame, said brush holder being of U-shaped configuration, having a projecting lug adjacent its bight portion adapted to receive and position said brush; means for securing said brush to said holder, said brush holder having aligned openings formed with converging walls engageable With the pin; and resilient means for urging said brush holder into predetermined pivotal relationship with respect to said commutator.

10. A brush supporting structure for dynamoelectric machines including a support having a pivot member projecting therefrom; the brush holder comprising a U-shaped member; means formed adjacent the bight portion of the U- shaped member for positioning and retaining a brush structure, the projecting leg portions being formed with slots having converging walls for engagement with the pivot member.

11. A brush supporting structure for dynamoelectric machines comprising a plate; a pivot pin carried by said plate; a U-shaped member; means formed adjacent the bight portion of the U- shaped member for positioning a brush structure; means formed on said member for receiving brush retaining means, the projecting legs of said U-shaped member having openings therein to receive and accommodate said pin, the walls of said openings being shaped to provide a two-line contact with said pin; and a resilient member encircling said pin for applying pressure in one direction to said U-shaped member.

HARRY R. PATTERSON. 

